Modern submarines need the capability to launch torpedoes while underway. These undersea craft usually have fairing-like structures that cover the torpedo tubes to reduce turbulence and associated hull generated noise. The structures are removed before torpedoes can be launched. The mechanisms required to move the structures may be too heavy and bulky if they must not only move the weight of the structure but also overcome the pressure created across the sides of the structures due to hydrodynamic flow over the structure""s surfaces.
Thus, in accordance with this inventive concept, a need has been recognized in the state of the art for an apparatus for reducing the total force needed to open shutters covering torpedo tubes so that torpedoes may be launched while underway at high speeds.
An object of the invention is to provide an apparatus for reducing the force necessary to displace a shutter from its open to closed position and back.
Another object of the invention is to provide an apparatus for eliminating pressure imbalance across a shutter to reduce the force necessary to displace it.
Another object of the invention is to provide an apparatus for reducing force to displace a shutter from the muzzle of a torpedo tube that virtually eliminates influences of speed of the submarine.
Another object of the invention is to provide an apparatus for reducing force to displace a shutter from the muzzle of a torpedo tube that is automatic and, therefore, free from potential operator error.
Another object of the invention is to provide an apparatus for reducing force to displace a shutter from the muzzle of a torpedo tube which simplifies connecting linkages and decreases manufacturing cost.
Another object of the invention is to provide cost-effective two-way valves in a shutter that eliminate pressure differentials from being developed across the shutter.
Another object of the invention is to provide pressure relief valves in a shutter that eliminate pressure differentials attributed to water flow on the side of the shutter adjacent the ambient ocean.
These and other objects of the invention will become more readily apparent from the ensuing specification when taken in conjunction with the appended claims.
The present invention provides an apparatus for reducing force needed to displace a shutter covering a torpedo tube while the vessel is underway at high speeds. A plurality of pressure relief valves are mounted in the shutter and each has a retaining ring secured in a lateral aperture in the shutter. A central portion of the relief valve has an annular rim portion positioned in the shutter lateral aperture. A first end portion at one end of the central portion is provided with a first end surface extending in a first aperture in the shutter. The first aperture is coaxial with and in communication with the lateral aperture. A second end portion at the opposite end of said central portion is provided with a second end surface extending in the retaining ring aperture. A first biasing spring is positioned in the lateral aperture between the shutter and a first side of the annular rim portion, and a second biasing spring is positioned in the lateral aperture between a second side of the annular rim portion and the retaining ring. These springs hold the first end surface coplanar with a top surface of the shutter and the second end surface coplanar with a bottom surface of the shutter thereby preventing generation of objectionable levels of flow noise.